Here's a link to the pto safety switch
New Holland BOOMER 1025 - COMPACT TRACTOR(05/08 - 12/08) Parts Diagrams
A new switch only costs about 73 bucks an doesn't look too overly hard to replace.
Sounds like you got a mower deck problem. Your not using mulching blades are you. Also are the exhaust vents on the vac units open and flowing air.
I have a Cyclone rake and that thing does a super good job of sucking up leave and grass clipping plus walnuts and hickory nuts that go thru the mower.
I got a new XL model in March.
The first time I used it the grass was nice an green and lush. I filled the hopper about 3/4 maybe a little less, then full. Went to unload. Just to heavy to pickup and dump. Ended up raking the grass out till I could lift it. The second load which was about 1/2...